China drivers now buy more cars than those in any other country and the market is a key for luxury car sales. It is seen as a key to Tesla meeting its forecasts of continued increases in sales.

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"It's the largest luxury vehicle market in the world, and it's no secret that is where some of the premium European brands make all their money," said Craig Irwin, analyst for Wedbush Securities. "So how Tesla sales are taking shape in China is very important."

Tesla entered the Chinese market this year. Sales in China are helped by a subsidy of between $5,780 to $9,900 for buyers of electric cars.